Fuel injector for internalcombustion engines



May 17, 1949. 2,470,717

FUEL mjsq'ron ron m'rmamn bbuaus'nou ENGINES v v. PALUMBO I ll]! oz iginal Filed March 16, 1944 mmvrox, Vlkcewfi Pa/u/nba. dwiMw Army Patented May 17, 1949 UNITED STATES PATENT OFFICE FUEL INJECTOR FOR INTERNAL- COMBUSTION ENGINES Vincent Palumbo, Cleveland Heights, Ohio Original application March 16, 1944, Serial No.

526,696. Divided and this application September 5, 1946, Serial No. 694,949

7 Claims. 1

My invention relates to fuel injection means for internal combustion engines, the present application being a division of one filed March 16, 1e44, Serial No. 526,696.

Among the objects of the invention is that of providing a fuel injector so designed as to simplify, cheapen and facilitate production and assembly of its parts, and to increase the efficiency, durability and reliability of the device.

The foregoing objects, and others hereinafter appearing, are attained in the construction illustrated in the accompanying drawing wherein Fig.

1 is an elevational view of the injector, showing it applied to a fragment of a wall which is that of an internal combustion engine; Fig. 2 is a section through the fuel injector in the plane of its longitudinal axis, as indicated by the line 2-2 of Fig. 3, and Fig. 3 is a transverse section on the line 33 of Fig. 2.

The injector comprises two casing members designated in the drawing by the reference numerals I and 2. The casing member 2 has an axial threaded boss 3 which, as shown in Fig. 1, is screwed into a threaded aperture in the wall A that encloses the combustion space or cylinder of an internal combustion engine. Said aperture is flared at its inner end where it opens into said space or cylinder.

The casing member 2 encloses a chamber 4 which constitutes, and shall therefor be referred to herein at times as, the valve opening working space. A flat annular shoulder or seat 5 surrounds the open side of the chamber 4, and above the plane of said shoulder or seat, the casing member 2 is internally threaded for the reception of the reduced externally threaded lower end 6 of the casing member I. The peripheral portion of a flexible diaphragm l is clamped between the shoulder or seat I and a ring-like element 8 that fits within a relatively shallow circular recess in the bottom of the casing member I. A channel 9 extends about, and opens through the top face of the element 8, and surrounded by said element is a chamber iii, the bottom wall of which is formed by the diaphragm I. Said chamber ill constitutes a valve closing working space, and shall, at times, be so referred to.

Fuel is admitted to the channel 9 through a passage II from a pipe I2 that leads from a suitable source of liquid fuel (not shown); and from the channel 8 the fuel passes through registering apertures 12 and I4 in the element 8 and diaphragm 1, respectively, to a well l5 in the casing member 2. Said well communicates ass-107.6)

through a relatively large passage 16 with the valve opening working space or chamber 4. A

bleeder port ll of small cross sectional area establishes constant restricted communication between the channel 9 and the valve closing working space or chamber Ill. A dowel I8 serves to locate the element 8, diaphragm 1 and casing member 2 in such relation to one another that theapertures l8 and i4 and the well I5 are in register.

A relatively large bore 20 leads from the valve opening working space or chamber 4 the greater part of the distance through, and axially of the boss 3, and adjacent-the lower end of-the boss said bore is reduced in diameter to provide an outlet orifice 2|. The upper end of said orifice is surrounded by a valve seat 22, and arranged for cooperation with said seat is a valve 23 that is provided with an extension 24 which occupies and is slightly less in diameter than the orifice 2| so as to produce, with the wall of the orifice, a narrow annular slot through which fuel is adapted to be injected into the combustion space or cylinder of the engine when the valve 23 is lifted from its seat. By reason of the construction just described, an orifice of the required effective small cross sectional area is provided, and yet in actual diameter it is sufllciently large to avoid difilculties attending the drilling and the functioning of a very small orifice. In this connection, it may be explained that the scale to which the drawing is made is very considerably enlarged over actual size. The stem of the valve is designated 25 and the portion thereof occupying the bore 20 is formed with wings 26 that have easy working fit within the bore and serve to maintain the valve 23 in concentric relation to its seat 22. The stem 25, above a flange 2l thereon, is projected through a central aperture in the diaphragm 1. A washer 28 is applied to the stem above the diaphragm and, by a peened over portion of the stem, is held. in peeltion to clamp the diaphragm tightly between it and the flange 21 and produce a leakproof joint. Above the washer 28 the stem is shown as reduced in diameter where it is surrounded by a spring 29 that is compressed between an abutment portion fixed with respect to the diaphragm and a stop .30 that is threaded in the upper end of an axial bore 3| of the casing member I. The stop may be adjusted through the medium of a stem 32 that is surrounded by a gland nut 33.

A second passage 35 in the upper casing member I communicates with the valve closing working space or chamber Ill and, through a pipe 36,

with actuating means (not shown, but which is fully disclosed in the above mentioned application where said means is termed a pulsator).

Reference to the parent application would show that the above described injector forms a part of a fuel feeding and control system which includes, with a source of liquid fuel that is maintained under a substantially constant pressure, a structure comprising the injector, the aforesaid pipes 12 and 36, and the actuator or pulsator (not shown), and that said structure provides a primary and a secondary enclosure, in the former of which is contained a body of fuel extending from said source to the outlet orifice 2| of the injector, and to a portion of which body of fuel, contained in the valve opening working space, one side of the diaphragm I is exposed, the pressure of said body tending to move the diaphragm in a direction to lift the valve 23 from its seat. A second body of fuel is confined in said secondary enclosure, and to portion of this second body of fuel, present in the valve closing working space, is exposed the opposite side of the diaphragm I. Equilibrium between the two bodies of liquid that occupy said primary and secondary enclosures is attained through the bleeder port ll. Also, through said port, equilibrium between said bodies is restored with comparative slowness (due to the size of the bleeder port) when, at intervals, said equilibrium is disturbed.

The beforementioned actuator means or pulsator (not shown) is characterized by a movable wall or diaphragm, and it forms a part of the secondary enclosure. When said wall or diaphragm of the pulsator is reciprocated or vibrated by suitable means, it intermittently and momentar ily disturbs the aforesaid equilibrium between said two bodies of fuel, thereby permitting the momentarily superior pressure of the first mentioned body to lift the diaphragm I and open the valve 23 so as to admit a charge of fuel to the combustion space or cylinder of the engine.

Having thus described my invention, what I claim is:

l. A fuel injector for internal combustion engines comprising a diaphragm means including a peripheral holding part and a working part, a valve having operative connection with said working part of the diaphragm means, a casing member enclosing a valve opening working space and a shoulder surrounding an open side of said space and wherewith the peripheral holding part of the diaphragm means is engaged, said casing member having an outlet orifice in operative relation to which said valve is disposed, a ring-like element engaged with the peripheral holding part of the diaphragm means on the side thereof opposite said shoulder, said element having a recess that opens through the face of the element opposite that engaging said holding part, a second casing member arranged in face-to-face relation with the first casing member, means for holding the two casing members together with said holding part clamped between said shoulder and the ring-like element, the space surrounded by said ring-like element constituting a valve closing working space, the second mentioned casing member including an inlet passage that opens into said recess and a relief passage that opens into the valve closing working space, there being passageways through which communication is established between said recess and the valve opening working space, and there being also a bleeder port through which communication is established between said working spaces, the cross sectional area of which port is substantially smaller than that of said passageways.

2. A fuel injector for internal combustion engines comprising a diaphragm means including a peripheral holding part and a working part, a valve carried by said working part of the diaphragm means, a casing member enclosing a valve opening working space and a shoulder surrounding an open side of said space and wherewith the peripheral holding part of the diaphragm means is engaged, said casing member having an outlet orifice in operative relation to which said valve is disposed, a ring-like element engaged with the peripheral holding part of the diaphragm means on the side thereof opposite said shoulder, said element having an annular channel that opens through the face of the element opposite that engaging said holding part, a second casing member arranged in face-to-face relation with the first casing member, means for drawing the two casing members toward each other with said holding part clamped between said shoulder and the ring-like element, the space surrounded by said ring-like element constituting a valve closing working space, the second mentioned casing member including an inlet passage that opens into said channel and a relief passage that opens into the valve closing working space, the ring-like element, diaphragm means and first mentioned casing member having passageways through which communication is established between said-channel and the valve opening working space, there being a bleeder port through which communication is established between said working spaces and the cross sectional area of which port is substantially smaller than that of said passageways.

3. A fuel injector for internal combustion engines comprising a diaphragm means including a eripheral holding part and a working part, the latter having an aperture, a valve including a stem extended through said aperture and sealed therein, a casing member enclosing a valve opening working space that opens through a face of the casing member and said casing member being provided with an .annular seat surrounding the open side of said space and wherewith said holding part of the diaphragm means is engaged, said casing member including a hollow boss into the bore of which the stem of the valve projects and which is considerably larger in diameter than said stem, guide means by which the stem is maintained substantially central of said bore,

an orifice opening from said bore through the outer end of said boss, a valve seat surrounding the orifice at the end thereof adjacent said bore, a valve part on said stem for engagement'with said seat, a ring-like element engaging the peripheral holding part of the diaphragm means on the side thereof opposite that engaging said annular seat, said element being provided on its side opposite the holding part of the diaphragm means with an annular channel, the casing member extending beyond the plane of said annular seat and being internally threaded, a second casing member having an externally threaded end screwed into the first mentioned casing member, the ring-like element enclosing a valve closing working space and including a bleeder port through which said channel and said valve closing working space communicate, the second casing member being provided with an inlet passage that opens into said channel and with a relief passage that opens into the valve closing working space, the said ring-like element, diaphragm means and first casing member having passageways through which the channel communicates with the valve opening working space, said bleeder port having a cross sectional area that is considerably smaller than that of said passages and passageways.

'4. A fuel injector for internal combustion engines comprising a diaphragm means including a peripheral holding part and a working part, a valve having operative connection with said working part 01' the diaphragm, a casing member enclosing a valve opening working space that opens through a face of the casing member and said casing member being provided with an annular seat surrounding the open side of said space and wherewith said holding part of the diaphragm means is engaged, said casing member having a bore into which the stem of the valve projects and which is of greater cross-sectional area than said stem, and an orifice opening from said bore, a valve seat surrounding the orifice at the end thereof adjacent said bore, a valve part on said stem for engagement with said seat and an extension beyond said valve part that occupies said orifice and is disposed in spaced relation to the peripheral wall thereof, a ring-like element engaging the peripheral holding part of the diaphragm means on the side thereof opposite that engaging said annular seat, said element being provided on its side opposite the diaphragm with a recess, the casing member extending beyond the plane of said annular seat,- a second casing member engaged with the first mentioned casing member and recessed to receive said ring-like element, means holding the casing members togather, the ring-like element enclosing a valve closing working space, the second casing member being provided with an inlet passage that opens into said recess and with a relief passage that opens into the valve closing working space, there being passageways through which said recess communicates with the valve opening working space, and there being also a bleeder port through which communication is established between said working spaces, said bleeder port having a cross sectional area that is considerably smaller than that of said passages'and passageways.

5. A fuel injector for internal combustion engines comprising a diaphragm means including a peripheral holding part and a working part, the latter having an aperture, a valve including a stem extended through said aperture and sealed therein, a casing member enclosing a valve opening working space that .opens through a face of the casing member and said casing member being provided with an annular seat surrounding the open side of said space and wherewith said holding part of the diaphragm means is engaged, said casing member including a hollow boss into the bore of which the stem of the valve projects and which is considerably larger in diameter than said stem. uide means by which the stem is maintained substantially central of said bore, an oriiice opening from said bore through the outer end of said boss, a valve seat surrounding the orifice at the end thereof adjacent said bore, a valve part on said stem for engagement with said seat and an extension beyond said, valve part that occupies said orifice and is disposed in spaced relation to the peripheral wall thereof, a ring-like element engaging the peripheral holding part of the diaphragm means on the side thereof opposite that engaging said annular seat,

the diaphragm with an annular channel, the easing member extending beyond the plane of said annular seat and being internally threaded, a second casing member having an externally threaded end screwed into the first mentioned casing member and recessed to receive said ringlike element, the ring-like element enclosing a valve closing working space and including a bleeder port through which said channel and said valve closing working space communicate, the second casing member being provided with an inlet passage that opens into said channel and with a relief passage that opens into the valve closing working space, the said ring-like element. diaphragm means and first casing member having passageways through which the channel communicates with the valve opening working space, said bleeder port having a cross sectional area that is considerably smaller than that of said passages and passageways.

6. A fuel injector for internal combustion engines comprising a diaphragm means including a peripheral holding part and a working part, the latter having an aperture, a valve including a stem extended through said aperture and sealed to said working part of the diaphragm means, a casing member enclosing a valve opening working space that opens through a face of the casing member and provided with an annular seat surrounding the open side of said space and wherewith said holding part of the diaphragm means is engaged, said casing member having a bore into which the stem of thevalve projects and which is considerably larger in cross sectional area than said stem, and an orifice opening from said bore, a valve seat surrounding the orifice at the end thereof adjacent said bore, a valve part on said stem for engagement with said seat, a ring-like element engaging the peripheral holding part 'of the diaphragm means on the side thereof opposite that engaging said annular seat, said element being provided on its side opposite said holding part with a recess, a second casing member engaged with first mentioned casing member, means holding the casing members together, the ring-like element enclosing a valve closing working space, the second casing member being provided with an inlet passage that opens into said recess and with a relief passage that opens into the valve closing working space, there being passageways through which the aforesaid recess communicates with the valve opening working space, and there being also a bleeder port through which communication is established between said workin spaces and which has a cross sectional area that is considerably smaller than that of said passages and passageways, the second casing member having a bore in axial alignment with the valve stem, a stop adjustable within said bore, and a spring sursounding the adjacent end of the valve stem and interposed between an abutment portion fixed with respect to the working part of the diaphragm means and an abutment portion associated with the second casing member.

7. A fuel injector for internal combustion engines comprising a diaphragm means including a peripheral holding part and a working part, the latter having an aperture, a valve including a stem extended-through said aperture and sealed to said working part of the diaphragm means, a casing member enclosing a valve opening working space that opens through a face of the casing member and provided with an annular seat sur- --said element being provided on its side opposite 1g rounding the open side of said space and wherewith said holding part of the diaphragm means is engaged,'said casing member including a ho]- low boss into the bore of which the stem of the valve projects and which is considerably larger in diameter than said stem, an orifice opening from said bore through the outer end of said boss, a valve seat surrounding the orifice at the end thereof adJacent said bore, ,a valve part on said stern for engagement with said seat, a ringlike element engaging the peripheral holding part of the diaphragm'means on the side thereof opposite that engaging said annular seat, said element being provided on its side opposite said holding part with an annular channel, the casing member extending beyond the plane of said anmilar seat and being internally threaded, a second casing member having an externally threaded end screwed into the first mentioned casing member, the ring-like element enclosing a valve closing working space and including a bleeder port through which said channel and said valve clos- 82 ing working space communicate, the second casing member being provided with an inlet passage that opens into said channel and with a relief passage that opens into the valve closing working space, the said ring-like element, diaphragm means and first casing member having passageways through which the channel communicates with the valve opening working space, said bleeder port having a cross sectional area that is considerably smaller than that of said passages and passageways, the second casing member having a bore in axial alignment with the valve stem, a stop adjustable within said bore, and a spring surrounding the adjacent end of the valve stem and interposed between an abutment portion fixed with respect to the working part of the diaphragm means and an abutment portion associated with the second casing member.

- VINCENT PALUMBQ- No references cited. 

